Hello,

i have a question about CF timing.

i'm using stock timing map. my boost is 1.4bar and wot AFR 11.5s. actual timing looks like as 11-12degree on vagcom. @6500rpm

But my CF values higher than 6... some times 7.5... how do i tune correctly ? i don't want reduce timing advance.

may be due to wrongly scaled maf ? or high pressure... ? wrong tvub ? or none , is it normal.. you can go to reduce timing.. or going to meth injection...

I'm confused...i don't want to see bigger than 3 CF..

my ecu is motronic 3.83 i know most people doesn't have a information about motronic 3x. but it something similar with m7x..

How can i reduce my CF's ? ( i don't want touch knock sensitivity maps)

Thank you

Kind Regards,

what's your CFs ? what's the optimal values ? bosch recomended..

also is this situation related with wrongly tuned maps ? for example i have  a stock TVUB map. and i'm using 3" maf housing with oem maf. 1x256k maf had been rescaled % increase.

I know these suggestions. but  i want to sure from my tuned maps. i know, there is a no more people's about motronic 3x.. 

Thank you.

You've increased load (boost) without modifying your timing map.  This means that you're likely pushing load values into the 200's, while utilizing a stock KFZW with an axis that maxes out at 150.  This means your timing is specifying values that would be normal at a load of 150% but insane at a load of 210%, thus the ECU retards timing heavily.

Yes, exactly.. I suspect it. but i don't have a any idea how can i scale it ?  Can i recale Y axis to 12ms's . but i think this is can be very dangerous. and i never seen good tuned KFZW map on motronic 3x.(with axis scaled)


also i think it's might be maf scaling.. if engine load calculated wrongly, i'll see abnormal retard values.. but i don't know How can I be sure, i made correctly scaled ?


Thank you for your comments

It's pretty simple, you are running too much boost and timing for your setup.
If you were tuning a standalone without amazing knock control like Motronic has, you would have melted your engine by now.
If you continue like this you will probably damage the exhaust valves and possibly the turbocharger due to huge EGT's.

Think a bit about this.

Tuning an internal combustion engine is not like playing need for speed. There are physical processes behind things, and it is a very good idea to understand them, before making changes to the engine management!

Depends on the engine, some make the most power as rich as 0.75 lambda.

But VAG 1.8T's tend to make most power at about 0.82-0.8, going richer to about 0.77 if advancing timing as well, does not tend to hurt performance, anything richer than that starts hurting performance even with advanced timing.

Of course this is speaking about a fairly stock engine...

And rescale the values I assume?
Is there other axises which should be generally scaled on ME7.5?
I´ve already scaled the KFZWOP(/2) axis and values to match the rescaled KFMIOP (for raised KFMIRL).
KFLBTS should be fine with the original load axis as it is rich enough @ 150%?

I do not get the reference that my friend, because TT225 has a me7x ecu.


Yes,right.. i'm reading bosch engine management documents etc..
i'll try reduce a bit ignition @highloads.





i had a 12s and i don't have a any problem. but fuel quality big factor for good timing. therefore I went back to 11.5s. i'm looking all situations..

I have a NGK 7x spark plugs. i think 8 more extreme for my setup.

Yes we don't have a any information about motronic 3 torque model and management..Nobody does not share information.longer an old ecu.. very interesting...

I think, talking about it.

i did rescale KFZW map X axsis. please find in attachment. just change, i changed map offset & factor value. old value 0.050000 new value is 0.060000.. correct or wrong.. it just example.

now it's going to 12ms load. But now advance timing all over the place. it can be dangerous. we need good tuned KFZW map or engine torque model... I have not seen a axis scaled KFZW map...

The summary,

CF's not good and not bad. but it maybe better.

physical factors can reduce it .. low iat,high octane,meth injection etc.,colder sparks,coilpack upgrades..We all know it.

it can lead to incorrect tuned maps ? load request (Kennfeld LDR-Sollwert,Linearisierung der Heißfilmspannung, etc) or fueling.. ?

i cannot see fuel trims on my me3x.. therefore I can not find the reference and can not be sure.


I think the topic would be helpful for everyone.


Thank you for all the comments.

Regards,